Core is a direct source and carrier of information about rock properties and conditions of their formation. Core sampling and analysis are required to understand the composition and structure of the geological target and to identify and allocate the reservoir. Integrated and coherent core analysis provides the most comprehensive information on the lithological structure of the cross-sections.
CJSC MiMGO performs a full range of core analysis, from detailed description to petrophysical modeling.
Core handling begins at the core storage where detailed layer-by-layer macro description of the core and its photographing are carried out. Sampling is carried out for a set of lab analyses of the lithological, mineral and petrophysical properties of the rocks. Then the core survey data are consolidated and summarized by comparing them with well logging data, creating graphical sedimentological well sheets (the sheets include well logging data, lithological rock description with textural and structural features, description of macrofauna remnants, trace fossil types and bioturbation intensity, layer and member boundaries, displaying heterogeneities and core inclusions, etc.). Graphical sheets as a form of comprehensive data presentation allow to compare all available information, analyse reservoir rock properties, identify productive intervals and measure the intensity of secondary transformations and their impact on the rocks filtration and volumetric properties. The analysis of lithological rock types distribution both along the extension and vertically identifies their stable paragenesis, which helps to reveal the strata facies structure.
Core and well logging analysis identifies depositional cyclites which correlate with the main sedimentation stages. The lithological and facies analysis identifies the main sedimentary facies types and deposition conditions, enabling building of a conceptual sedimentological model and facies maps.
Obtained facies maps and change patterns of facies associations are used in borehole and seismic data interpretation to enhance the reliability and validity of the resulting geological modeling. The identified patterns of facies association distribution along the cross-section will influence the production well pads drilling. Sedimentological core analysis and lithological-facial studies establish algorithms and adjust forecasting methodologies for filtration and volumetric properties.
An integrated approach to core analysis reveals information about the cross-section geological structure and its oil and gas bearing capacity, the reservoir and cap rocks location in the cross-section and their spatial variations, and the HC distribution in the reservoirs.
